液相色谱串联质谱法测定茶叶中氯虫苯甲酰胺残留量

目的 建立液相色谱-串联质谱法检测茶叶中氯虫苯甲酰胺残留量的方法。方法 样品采用乙腈振荡超声提取, HLB固相萃取柱净化, 液相色谱串联质谱检测, 外标法定量。结果 方法的线性范围为0.50~ 20.00 ng/mL, 相关系数r2大于0.999; 检出限为 0.05 μg/kg, 定量限为0.17 μg/kg。在不同基质中, 氯虫苯甲酰胺在0.20、0.40、2.00 μg/kg添加水平下的平均回收率为79.25%~88.42%, 相对偏差为1.50%~7.10%。结论 该方法具有快速简便、灵敏度高、准确性强等特点, 适用于茶叶中氯虫苯甲酰胺残留量的检测。     

超高效液相色谱-串联质谱法测定干辣椒中2种新型杀虫剂残留量

目的 建立超高效液相色谱-串联质谱法(ultra performance liquid chromatography-tandem mass spectrometry, UPLC-MS/MS)测定干辣椒中氰氟虫腙和氯虫苯甲酰胺残留量的分析方法。方法 干辣椒样品经乙腈匀浆提取, 氨基固相萃取小柱净化, 甲醇/水(50:50, V:V)定容, 以反相C18色谱柱(100 mm×2.1 mm, 1.7 μm)分离, 0.1%甲酸-水和甲醇作为流动相进行梯度洗脱, 多反应监测模式下进行超高效液相色谱-串联质谱测定、基质匹配标准溶液外标法定量。结果 2种新型杀虫剂在5~500 μg /L范围内线性关系良好, 相关系数均大于0.999, 定量限为0.008~0.01 mg /kg; 在高、中、低3个加标水平下的回收率为80.4%~94.9%, 相对标准偏差在0.9%~8.7%之间。结论 方法简单、快速、灵敏高、准确可靠, 可操作性强, 适合测定干辣椒中氰氟虫腙和氯虫苯甲酰胺残留量。     

液相色谱-串联质谱法同时测定瓜类蔬菜及粮谷中8种农药的残留量

目的 建立液相色谱-串联质谱法同时检测GB 2763-2016中无推荐检测方法的8种农药(氟啶虫酰胺、氯噻啉、氟啶虫胺腈、氯虫苯甲酰胺、螺虫乙酯、丙硫克百威、氰氟虫腙、除虫菊素I)多残留检测方法。方法 样品以乙腈:甲酸(99:1, V:V)作为提取剂, 经QuEchERS方法前处理, 采用Kinetex C18色谱柱 (50 mm×2.1 mm, 2.6 μm, 100 ?)分离, 以乙腈和0.1%甲酸溶液为流动相梯度洗脱, 柱温为30 ℃, 流速为400 μL/min, 采用多反应监测模式检测, 外标法定量。结果 8种农药在浓度为5~200 μg/kg范围内线性关系良好, 相关系数均大于0.99。平均加标回收率率为80.5%~109.2%, 相对标准偏差为2.7%~26.3%, 8种农药的定量限为0.5~10 μg/kg, 符合残留分析的要求。结论 该方法操作简便, 适用于瓜类蔬菜及粮谷中8种农药残留量的同时测定。     

分散固相萃取净化离子色谱-串联质谱测定茶叶中高氯酸盐

目的 建立分散固相萃取净化离子色谱-串联质谱法测定茶叶中高氯酸盐的含量。方法 样品经80 ℃超纯水浸泡提取30 min, 定性滤纸过滤, 滤液采用分散固相萃取技术, 以多壁碳纳米管和N-丙基乙二胺键合固相吸附剂吸附提取液中的杂质, 待测样品由离子色谱-串联质谱法测定, 内标法定量。结果 高氯酸盐浓度0.02~10.00 μg/L有良好的线性关系, 相关系数r2为0.9998, 检出限为0.6 μg/kg, 定量限为2.0 μg/kg, 加标回收率为80.1%~99.2%, 相对标准偏差为3.89%~7.68% (n=6)。对市场上随机购买的茶叶样品进行测定, 样品的含量为0.15~0.72 mg/kg。结论 该方法简便、可靠、稳定、灵敏度高, 可用于茶叶中高氯酸盐快速检测。     

高效液相色谱-串联质谱法和高效液相色谱法测定蜂蜜中氯虫苯甲酰胺残留量

目的建立通过一次样品前处理,可供高效液相色谱-串联质谱法(high performance liquid chromatography-tandem mass spectrometry,HPLC-MS/MS)和高效液相色谱法(high performance liquid chromatography,HPLC)2种仪器检测蜂蜜中氯虫苯甲酰胺残留量的方法。方法试样经1%乙酸水溶解,乙酸乙酯萃取,氮吹浓缩,乙腈-水(1:1,V:V)复溶,供仪器检测,外标法定量。结果高效液相色谱-串联质谱法在1.25~50.00μg/L范围内线性相关性良好,相关系数r²为0.9996;在1、2、5μg/kg质量浓度水平下的加标回收率为90.5%~105.9%,相对标准偏差为2.9%~4.6%(n=6);检出限为0.5μg/kg,定量限为1.0μg/kg。高效液相色谱法在25~1000μg/L范围内线性相关性良好,相关系数r2为0.9995;在20.0、50.0、100.0μg/kg质量浓度水平下的加标回收率为94.6%~104.4%,相对标准偏差为1.6%~2.9%(n=6);检出限为10μg/kg,定量限为20μg/kg。结论本方法快速、准确、灵敏,适用于蜂蜜中氯虫苯甲酰胺残留量的测定。     

多壁碳纳米管固相萃取净化-气相色谱质谱联用 同时测定茶叶中26种农药

目的建立一种多壁碳纳米管固相萃取净化-气相色谱质谱联用同时测定茶叶中26种农药的检测方法。方法样品经乙腈提取,过滤型多壁碳纳米管柱净化后,使用气相色谱质谱仪检测。结果碳纳米管净化能够有效去除茶叶中干扰物质,简化实验步骤,降低前处理过程中农药的分解。26种农药在0.04~1.6μg/m L范围内具有较好的线性。方法的检出限为0.005~0.05 mg/kg,定量下限为0.015~0.15 mg/kg。采用该方法对茶叶样品进行加标回收率实验,加标回收率在66.6%~125.5%,相对标准偏差为0.3%~6.4%(n=5)。结论该方法快速、准确、灵敏,适合茶叶中多种农药的同时测定。     

QuEChERS-超高效液相色谱-串联质谱法同时测定动物源性食品中5种双酰胺类杀虫剂的残留

目的 采用超高效液相色谱-串联质谱方法检测猪肉、猪肝、鸭肉、鸡肉和鱼肉等动物源性食品中5种双酰胺类杀虫剂(氟苯虫酰胺、氯虫苯甲酰胺、溴氰虫酰胺、四氯虫酰胺、环溴虫酰胺)的残留量。方法 采用QuEChERS样品前处理技术,样品经乙腈水提取,提取液用1 g无水硫酸镁和2 g氯化钠脱水,150 mg N-丙基乙二胺、150 mg C₁₈和400 mg无水硫酸镁净化,以乙腈-5 mmol/L乙酸铵溶液作为流动相,经ACQUITY UPLC BEH C₁₈色谱柱梯度洗脱分离,电喷雾离子源离子化,负离子多反应监测模式检测。结果 5种双酰胺类杀虫剂在2～50 ng/mL的质量浓度范围内线性关系良好,相关系数(r)大于0.999 0,在3.0 μg/kg、6.0 μg/kg和12.0 μg/kg 3个添加水平下,5种双酰胺类杀虫剂的回收率范围为79.6%～112.4%,相对标准偏差(relative standard deviations, RSD)为0.6%～6.9% (n=6),方法检出限和定量限范围分别为0.7～1.0 μg/kg和2.0～3.0 μg/kg。结论 本方法操作简单、灵敏度和准确度高、重现性好,可同时检测动物源性食品中5种双酰胺类杀虫剂的残留量,为其日常监管提供了技术支持。     

固相萃取-UPLC-MS/MS法测定牛奶中氟虫腈及其代谢物残留量

建立一种固相萃取-超高效液相色谱-串联质谱法同时测定牛奶中氟虫腈及其代谢物(氟甲腈、氟虫腈砜、氟虫腈硫醚)的分析方法。牛奶样品经提取和盐析,Oasis PRiME HLB固相萃取柱通过式净化后,以乙腈-水为流动相,HSS T3色谱柱(2.1mm×100 mm,1.8 μm)进行色谱分离,在电喷雾负离子模式下,多反应监测(MRM)方式进行测定,外标法定量。结果表明,氟虫腈及其代谢物在0.05~5.0 μg/L浓度范围内均呈良好的线性关系,相关系数r≥0.9976,方法检出限为0.01 μg/kg,定量限为0.05 μg/kg。在浓度分别为0.5、1、10 μg/kg加标水平下,4种化合物的回收率范围为80.6%~101%,相对标准偏差范围为1.0%~6.1%。该方法简单快捷、准确可靠,适用于牛奶中氟虫腈及其代谢物的同时测定。     

同位素稀释超高效液相色谱-串联质谱法测定山楂及其口服液制品中的展青霉素

目的 建立同位素稀释超高效液相色谱-串联质谱法测定山楂及其制品中的展青霉素含量。方法 山楂口服液(山楂样品需经粉碎、果胶酶酶解处理, 乙酸乙酯提取浓缩后复溶)经多功能净化柱净化, 以乙腈-水为流动相梯度洗脱, 采用Agilent RRHD C₁₈柱(2.1 mm×100 mm, 1.8 μm), 电喷雾离子源负离子, 多反应离子监测模式(MRM)检测, 同位素稀释内标法定量。结果 展青霉素在4.934~246.7 ng/mL浓度范围内线性关系良好, 相关系数r大于0.999。在不同基质不同加标浓度下, 回收率为91.8%~105.4%, 相对标准偏差为1.8%~3.2%, 山楂检出限为3 μg/kg、定量限为10 μg/kg, 山楂口服液检出限为1.5 μg/kg、定量限为5 μg/kg。结论 该方法准确、可靠, 适用于山楂制品中展青霉素的测定。     

液相色谱串联质谱法测定油料作物中3种双酰胺类杀虫剂残留量

目的建立液相色谱-串联质谱法测定油料作物中3种双酰胺类药物残留量的分析方法。方法油料作物样品经乙腈振荡超声提取,OasisPRiMEHLB固相萃取柱净化,液相色谱串联质谱测定,外标法定量。结果氯虫苯甲酰胺、氟苯虫酰胺、溴氰虫酰胺检出限分别为:0.050、0.010、0.010μg/kg,定量限分别为0.20、0.030、0.030μg/kg。在不同基质中,氯虫苯甲酰胺在0.20、0.40、2.0μg/kg添加水平下的平均回收率为78.4%～88.5%,相对标准偏差在1.7%～5.7%之间;氟苯虫酰胺、溴氰虫酰胺在0.030、0.060、0.30μg/kg添加水平下的平均回收率为79.9%～100.5%,相对标准偏差为1.1%～5.6%。结论该方法快速简便、灵敏度高、准确性强等特点,适用于油料作物中氯虫苯甲酰胺、氟苯虫酰胺、溴氰虫酰胺残留量的检测。     

Reliable identification of grapevine rootstock varieties using RAPD PCR on woody samples

Since grapevine ( Vitis spp .) rootstock material is being traded increasingly as disbudded woody material a lack of distinctive morphological features on such material necessitates an alternative and reliable means of identification. Methods described here were developed for rapid and efficient extraction of DNA from woody samples rich in phenolic compounds and polysaccharides, and for subsequent identification of varieties by RAPD PCR. Using these methods, and with the application of only one selected RAPD primer, we were able to differentiate sixteen rootstock varieties, including the seven varieties most commonly used in Germany. Problems commonly encountered with reproducibility of RAPD patterns were avoided by choosing primers with a dinucleotide sequence and a high G/C content that allowed a rather high annealing temperature of 45°C. Methods described here should also be useful for other horticultural crops, especially those with woody tissues rich in phenolic compounds and polysaccharides.     

Review of techniques to manufacture micro-hydrogel particles for the food industry and their applications

Microgels are ‘soft’ microscopic cross-linked polymeric particles that are being increasingly exploited in a variety of industries for rheology control, encapsulation and targeted delivery. They are valued because of the ability to tune their functionality to address specific applications in oil recovery, coatings, drug delivery, cosmetics, personal care and foods. Food microgels are typically biopolymer hydrogels in the form of microspheres, nanospheres (also called nanogels), spheroids and fibres. The utilisation of engineered microgels in foods has so far been limited, despite their great potential to address several needs in the food industry, including: satiety control, encapsulation of phytonutrients and prebiotics, texture control for healthier food formulations (e.g. reduced fat products), and targeting delivery to specific areas in the digestive tract. We review the scientific and patent literature on the utilisation and manufacturing methods for producing microgels with an emphasis on micro-hydrogels for food applications.     

12—A CRITIQUE OF SOME HYPOTHESES RELATING TO THE HETEROGENEITY OF THE HIGH-SULPHUR PROTEINS OF WOOL

Joubert and Burns prepared a large number of fractions from the high-sulphur proteins of wool and estimated their molecular weights and amino-acid compositions. Their data have been re-examined in order to look for statistically significant interrelations between amino acids and between the proportion of various amino acids and molecular weight. Statistical analysis of the data is also used to examine the credibility of some hypotheses concerning the mechanism of keratin biosynthesis and to provide further evidence for the existence of families of proteins within the high-sulphur fractions of wool.     

Announcing a new international peer-reviewed journal:Food Science and Human Wellness now accepting manuscript submission in English

<正>We are pleased to announce the launch of a new international peer-reviewed journal-Food Science and Human Wellness,ISSN 2213-4530,which is an open access journal,produced and hosted by Elsevier B.V.on behalf of Beijing Academy of Food Sciences.Food Science and Human Wellness is an international peer-reviewed English journal that provides a forum for the dissemination of     

The Latest Data about Development of Chinese Printing Industry in 2013

In the 2014 China（Shanghai）International Printing Week,Director Wang Yanbin released the latest data about development of Chinese printing industry in 2013.According to statistics,in 2013,the total output value of Chinese printing industry exceeded 1trillion Yuan for the first time,reaching 1.03985 trillion Yuan.There were 105,000 printing enterprises in China,employees were 3.415 million.The total asset was 1.06247 trillion Yuan;     

The State Council Issued "Directory of Government Approved Investment Projects(2013 Edition)"

正On December 2nd,2013,the State Council issued the notification of"Directory of Government Approved Investment Projects(2013 Edition)"(hereafter referred to as"notification").It is pointed out in the"notification"that in order to further deepen reforms in investment systems and administrative examination and approval systems,simplify administrative procedures and delegate powers to lower levels,earnestly     

Top Ten News of China's Paper Industry 2013

On December 24th, 2013, the meeting on the selection of top 10 news of China＇s paper industry 2013 sponsored by 〈China Paper Newsletters〉 was held in Beijing. The yearly selection of the top l0 news, which began in 2000, has become a brand activity widely recognized in the industry thanks to the support from the authorities at all levels and public participation.     

National Development and Reform Commission Issued Announcement for Selection of Major Preliminary Research Projects for the "13~(th) Five-Year Plan"

In Apri Commi major p Plan＂ （h 2014, the National Development and Reform ssion issued an announcement for selection of reliminary research projects for the ＂13th Five-Year ereafter referred to as ＂The Announcement＂）     

Announcing a new international peer-reviewed journal:Food Science and Human Wellness now accepting manuscript submission in English

<正>We are pleased to announce the launch of a new international peer-reviewed journal-Food Science and Human Wellness,ISSN 2213-4530,which is an open access journal,produced and hosted by Elsevier B.V.on behalf of Beijing Academy of Food Sciences.Food Science and Human Wellness is an international peer-reviewed English journal that provides a forum for the dissemination of the latest scientific     

China textile machinery: taking off in progress

正Among the 1600 exhibitors who take apart in the ITMA ASIA+CITME2014 2/3 are Chinese manufactures.If the numerous figures failed to attract your attention,the increase of quality should draw your focus.To adopt the demand of developing textile machine market,domestic textile machinery enterprises now follow the slogan of"technology drives development"to enhance product competitiveness.Our domestic sellers will showcase product ranging from spinning,weaving,dyeing and printing,